Taste receptors of the T1R family from domestic dog

Abstract

The present invention relates to the discovery of several genes of the domestic dog ( Canine familiaris ) associated with taste perception. The invention provides, inter alia, the nucleotide sequence of the canine Tas1r1, Tas1r2, and Tas1r3 receptor genes, the amino acid sequences of the polypeptides encoded thereby, and antibodies to the polypeptides. The present invention also relates to methods for screening for compounds that modify the genes' function or activity, the compounds identified by such screens, and mimetics of the identified compounds. The invention further provides methods for modifying the taste preferences, ingestive responses, or general behavior of a mammal such as a dog by administering compounds that affect the function or activity of the gene or the polypeptide encoded thereby.

1. An isolated and purified polynucleotide encoding a T1R receptor, said T1R receptor comprising the amino acid sequence of SEQ ID NO:3. 
     
     
       2. The polynucleotide of  claim 1 , wherein said polynucleotide is DNA. 
     
     
       3. The polynucleotide of  claim 1 , wherein said polynucleotide is RNA. 
     
     
       4. An expression vector comprising the polynucleotide of  claim 1  operably linked to a promoter. 
     
     
       5. A host cell comprising the expression vector of  claim 4 . 
     
     
       6. The host cell of  claim 5  wherein said cell is mammalian. 
     
     
       7. The host cell of  claim 6  wherein said cell is a human, murine, or canine cell. 
     
     
       8. The host cell of  claim 5  wherein said cell is bacterial. 
     
     
       9. A cell culture comprising at least one cell of  claim 5 . 
     
     
       10. A method of producing a canine T1R receptor comprising culturing the host cell of  claim 5  and recovering said receptor from said host cell. 
     
     
       11. The canine T1R receptor produced according to the method of  claim 10 . 
     
     
       12. An isolated and purified T1R receptor polypeptide comprising an amino acid sequence having 95% identity with SEQ ID NO:3. 
     
     
       13. An isolated and purified T1R1 receptor polypeptide comprising the amino acid sequence of SEQ ID NO:3. 
     
     
       14. An isolated and purified polynucleotide encoding a T1R receptor, said polynucleotide comprising a nucleic acid sequence having at least 95% identity to SEQ ID NO:1 or SEQ ID NO:2. 
     
     
       15. An isolated and purified T1R receptor comprising a T1R1 polypeptide comprising the amino acid sequence of SEQ ID NO:3 and a T1R3 polypeptide comprising the amino acid sequence of SEQ ID NO:9. 
     
     
       16. A method for identifying compounds that interact with a canine T1R receptor comprising:
 contacting a canine T1R receptor comprising a T1R1 polypeptide comprising the amino acid sequence of SEQ ID NO:3 and a T1R3 polypeptide comprising the amino acid sequence of SEQ ID NO:9 with a test compound, and 
 detecting interaction between said T1R receptor and said compound. 
 
     
     
       17. A method for identifying an agonist of a canine T1R receptor comprising:
 contacting a T1R receptor comprising a T1R1 polypeptide comprising the amino acid sequence of SEQ ID NO:3 and a T1R3 polypeptide comprising the amino acid sequence of SEQ ID NO:9 with a test compound, and 
 detecting an increase in biological activity of said T1R receptor in the presence of said compound relative to biological activity of said T1R receptor in the absence of said compound. 
 
     
     
       18. A method for identifying an antagonist of a canine T1R receptor comprising:
 contacting a T1R receptor comprising a T1R1 polypeptide comprising the amino acid sequence of SEQ ID NO:3 and a T1R3 polypeptide comprising the amino acid sequence of SEQ ID NO:9 with a test compound with a test compound, and 
 detecting a decrease in biological activity of said T1R receptor in the presence of said compound relative to biological activity of said T1R receptor in the absence of said compound.